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Homework Help: Find peak voltage across capacitor

  1. Jul 10, 2009 #1
    Hi everyone!

    I hope you people can help me out at a problem I am stuck with:

    1. The problem statement, all variables and given/known data

    Find the peak voltage across the capacitor "C"

    All variables given and an image of the circuit are:

    • http://img36.imageshack.us/img36/580/photo2fsc.jpg [Broken]
    • The circuit is connected to an AC battery of 25V labeled as "U" in the diagram.
    • Lightbulbs "L1" and "L2" use 5.5 W each
    • Lightbulbs "L3" and "L4" use 2 W each
    • All bulbs will light up if they each receive 4.5V (thats exactly how the question states it)
    • Resistance across point "A" and "B" is 5.4 Ohm

    2. The attempt at a solution

    To be honest - I don't even know where to start this problem. The only thing which I thought to do is to calculate the peak voltage of the battery. Which is 35.36V. The next step I thought to do is to calculate the voltage across the bulbs - however I don't have any current value.

    Any breadcrumbs to get me started would be great.
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jul 10, 2009 #2
    Do they give you the capacitance?
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